Technical Field
The present disclosure relates to multiple contact probe tests, and more specifically, to a method and system for disassembling a multiple contact probe head.
Related Art
Multiple contact probe heads are used to test integrated circuit wafers during fabrication. As shown in FIG. 1, each probe head 10 includes a number of contact probes 12, referred to occasionally as cobra probes or buckling beam probes, that are positioned in a predetermined pattern by an upper die 14 and a lower die 16. Each die includes a number of holes (not referenced) that position a respective end of the probes. Probes 12 extend from upper die 14 to a device interface board 18, e.g., a substrate attached to printed circuit board with a ball grid array, which provides electrical interconnections to a test controller (not shown) that runs tests using the probes. Probes 12 also extend from lower die 16 to contact a wafer 20 for electrical testing performed using the probes. Probes 12, as shown in FIG. 2, can extend in a predetermined two-dimensional pattern.
Periodically the probe head must be disassembled for cleaning or to replace individual damaged cobra probe wires. Conventional techniques to disassemble the probe head do not adequately attempt to maintain the position of the probes, which can lead to the probes becoming accidentally disengaged, damaged, soiled, etc. For example, as shown in FIG. 3, current techniques typically apply a layer of tape 22 across lower ends of probes 12 to hold the probes in place. This approach typically leads to many probes being accidentally removed, damaged probes and foreign material (e.g., tape residue, dust, etc.) collecting on the probes. Consequently, a task of replacing a certain number of probes can turn into replacing a large multiple of the number intended.